PowerShell for Office 365

Office 365 admin center is an out-of-the-box solution that is designed to handle the most common administrative tasks, such as creating new users and assigning licenses. There are situations where PowerShell for Office 365 helps us save time and effort. If you are a systems administrator, PowerShell is now a must-have skill. PowerShell for Office 365 helps you automate a lot of repetitive tasks and also work with advanced functions that are not available in Office 365 admin center:

I think using the Office 365 admin center is like using public transportation. We have to live with the options provided by Microsoft. If we need something custom, like in the case of transportation when we use taxis or personal vehicles, in Office 365, we can use PowerShell. We still have to write scripts in accordance with Microsoft's guidelines. However, we get far more flexibility and options as compared to Office 365 admin center.

Before we dive deep into PowerShell for Office 365, let's cover the basics of PowerShell in the next few sections.

The building blocks of PowerShell are called cmdlets (pronounced command-lets). Cmdlets allow us to get things done in PowerShell. A cmdlet is a lightweight command that is used in the Windows PowerShell environment. The Windows PowerShell runtime evokes these cmdlets within the context of automation scripts that are provided at the command line. We can put multiple cmdlets together into a set of commands to run all at once, or we can place them in a file with the extension .ps1 to create a PowerShell script that we can run manually or using a scheduler. In Office 365, the following cmdlets are commonly used:

In PowerShell, cmdlets follow a pattern with verb-noun syntax. For example, to manage users, the syntax is <Verb>-MSOL<Noun>.

Here, MSOL stands for Microsoft Online.

To manage SharePoint Online, the syntax is <Verb>-SPO<Noun>.

SPO is SharePoint Online.

The following is the list of the most commonly used verbs in PowerShell:

A cmdlet is a lightweight command that is used in the Windows PowerShell environment. The Windows PowerShell runtime invokes these cmdlets within the context of automation scripts that are provided at the command line. The Windows PowerShell runtime also invokes them programmatically through Windows PowerShell APIs.

They basically accept input via parameters, perform the operation, and then output the results.

Cmdlets differ from commands in a command-shell environment in the following ways:

Parameters

Parameters are the input values that we pass to a cmdlet. For example, if we have to get the time zone, we can use the following cmdlet:

Get-TimeZone

This cmdlet gets the current time zone or a list of available time zones.

These are the parameters:

• [-Id]: Specifies, as a string array, the ID or IDs of the time zones that this cmdlet gets
• [-ListAvailable]: Indicates that this cmdlet gets all available time zones
• [-Name]: Specifies, as a string array, the name or names of the time zones that this cmdlet gets

We can use this command with or without these parameters:

Get-TimeZone

The following screenshot shows the output for the preceding command:

We can use this command with the Name parameter:

Get-TimeZone -Name "*pac*"

The following screenshot shows the output for the preceding command:

We can use this command with the ListAvailable parameter:

Get-TimeZone -ListAvailable

The following screenshot shows the output for the preceding command:

In PowerShell, variables are always prefixed by the character $ and can include any alphanumeric character or underscore in their names. We can store the output from a cmdlet in a variable and use it later on in other cmdlets or for other purposes in the script, such as writing to the host, using it for comparison, or creating another variable, such as this, for example:

$timeZone = Get-TimeZone
Write-Host "The current time zone is " $timeZone

The following screenshot shows the output for the preceding command:

PowerShell comes with a lot of in-built cmdlets, and with the addition of every new module, the list of available cmdlets increases. You can use your favorite search engine to get more information on a cmdlet. You can do this from the PowerShell window as well. The cmdlet to get the help is this:

Get-Help nameofcmdlet

Here's an, for example:

Get-Help Get-Service

The following screenshot shows the output for the preceding command:

This is useful if we would like to get help but don't want to leave the Command Prompt.

If you would like to get help from the official online documentation, you can use the following cmdlet:

Get-Help Get-Service -online

This will open the online help manual of the cmdlet with your default browser:

If you would like to quickly check whether there are any commands available for a particular service, you can use the following cmdlet:

Get-Command *Service*

This will give all the commands that contain the Service service in all the modules that are loaded:

What is a module?

A module is a combination of multiple PowerShell functionalities like scripts, cmdlets that are built to solve a common purpose. For example, to work with the users and licensing, we have to use the Module MSOnline provided by the Microsoft. You can find more information about the Windows PowerShell module here https://msdn.microsoft.com/en-us/library/dd878324(v=vs.85).aspx.

To find out the members of a cmdlet, we can pipe the Get-Member cmdlet with another cmdlet:

Get-Service | Get-Member

The following screenshot shows the output for the preceding command:

PowerShell works with objects, and these objects can have attributes and methods. An attribute is a property or a description. PowerShell is an object-oriented scripting language; however, moderately complex scripts are often written using a procedural/functional approach.

To get the members of any cmdlet, we can pipe the Get-Member cmdlet with any given cmdlet:

Get-TimeZone | Get-Member

The output of the preceding command is shown in the following screenshot:

The type of the input is System.String[] and the type of the output is System.TimeZoneInfo[].

When writing scripts, we have to implement business logic that will shape the process. The if and where statements allow us to define logical conditions. For example, if you would like to compare two numbers, you can use the if and else statements and, based on the comparison, take appropriate action.

Conditional statements are the building blocks of any programming and scripting language.

If a certain condition is true, we can run a block of code. The syntax of an if...else is as follows:

if (<test1>)  
  {<statement list 1>} 
elseif (<test2>) 
  {<statement list 2>} 
else 
  {<statement list 3>}

Here's an example:

$a = 6;
 if( $a -eq 5){
   Write-Host "Variable a is equal to 5"
 }
 elseif( $a -eq 4){
   Write-Host "Variable a is equal to 4"
 }
 else
 {
   Write-host "Variable a is not equal to 5 and 4"
 }

The output of this script will be Variable a is not equal to 5 and 4.

We can use a combination of the if...else statements where in the if block we check for a condition: if that condition is true, then we execute a block of code, and if the condition is not true, then we execute another block of code. Sometimes, we can have more than one expected outcome and we can use multiple elseif conditions. The comparison operator -eq returns Boolean values (true or false). If the outcome of the comparison is true, then the associated block of code is executed. Since it is a Boolean value, we can use the reverse logic as well.

We have a lot of comparison operators available in PowerShell:

We can use multiple comparison operators in a single if statement. This helps you implement complex scenarios.

You can have multiple if statements or even use nested if statements.

We can Where-Object cmdlet to filter data return by other cmdlets. For example, if we would like to find out the processes running on a computer with the name svcHost we can use the Where-Object cmdlet with the Get-Process cmdlets as shown below.

Get-Process | Where-Object {$_.name -contains "svcHost"}

Loops in PowerShell execute a series of commands or cmdlets as long as the condition to run them is true. Loops are helpful for running repetitive tasks inside a PowerShell script. For example, if we need to create five new users, we can use a loop, and inside the loop, we can add the logic to create a new user and execute the loop five times. Loops allow us to write business logic once and then run it repetitively as long as a certain condition is met. To implement loops in PowerShell, we can use the for, foreach, while, do...while, and do...until loops.

In a for loop, we run the command block based on a conditional test. In the following for loop, we are running Write-Host until the value of variable $i is less than 5. In the beginning, the value of variable $i is 0, and every time the loop is executed, we are incrementing the value of $i by 1. During the execution of the loop, when the value of variable $i becomes 5, the loop stops executing:

for ( $i=0; $i -lt 5; $i++)
{
   Write-Host "Value of i is" $i
}

The output of this for loop is as follows:

Using the while, do...while, and do...until loops, we can run loops as long as a condition is true (it is met).

The while loops only use the while keyword, followed by the condition and then the script block, as shown here:

$i=1
 while ($i -le 10)
 {
   Write-Host "Value of i is" $i
   $i++
 }

In this script, the script block inside the while loop will run till the value of the variable $i is less than 10. The output of this while loop is as follows:

The do...while and do...until loops begin with the do keyword, followed by the script block and then by the conditional keyword and the condition.

Here's an example of the do...while loop:

$i=1
 do
 {
   Write-Host "Value of i is" $i
   $i++
 }
 while ($i -le 10)

Here's an example of the do...until loop:

$i=1
 do
 {
   Write-Host "Value of i is" $i
   $i++
 }
 until ($i -gt 10)

Both the examples mentioned here basically implement the same business logic using loops, with slightly different comparison methods. In the do...while loop, the script block will run until the value of the variable $i is less than 10, and in the do...until loop, the script block will run until the value of the variable $i becomes greater than 10. The output of both the loops will be the same as, shown here:

To automate tasks, we need to create and run PowerShell scripts. To run a script, we need to follow these steps:

Let's create our first PowerShell script. We will be creating a script to read the information from a CSV file and then process the information using the for loops and then print it on the screen.

A comma-separated file has information in the form of tables, as shown in the following screenshot. The file has the user's information: their first name, last name, location, and department. We will use this information and create the login names for the users using the format $firstName + "." + $lastName.

The CSV file is as follows:

The script is as follows:

Function generateUserName($firstName, $lastName){
  $userName = $firstName + "." + $lastName
  Return $userName;
}

$userInformation = import-csv 'C:\Demo\UsersInfo.csv'

foreach($user in $userInformation){
  $firstName = $user.FirstName
  $lastName=$user.LastName
  $department =$user.Department
  $office=$user.Office
  $Location=$user.Location
  $userName = generateUserName $firstName $lastName
  Write-Host "The generated user name is " $userName
}

The following screenshot shows the preceding script:

Now let's review this script line by line. As mentioned before, if you are using functions inside a script, it is recommended that you write them at the top of the script. The reason is that when the script is executed, the functions are already loaded.

On line 1 we have declared the function with the name generateUserName, and it accepts two parameters of type string. We can pass complex datatypes as parameters as well.

On line 2, we are creating the value for the username using the following logic:

$firstname + "." + $lastName

On line 3, we are returning that value.

On line 6, we are reading the contents of the CSV file. The Import-CSV cmdlet is a cmdlet to read the contents of a file.

We will be covering this cmdlet in detail because to automate bulk user creation, we can use $userInformation stored in CSV files. We can also use information from other sources, such as plain text files or SharePoint lists. But as of now, CSV files are more common.

The Import-CSV cmdlet reads the information from the .csv file and stores them in the table-like custom objects. Each column header becomes the property and the subsequent rows become the values of the properties. You can find more information about this cmdlet here https://msdn.microsoft.com/en-us/powershell/reference/5.0/microsoft.powershell.utility/import-csv.

Here is the Import-CSV command:

This cmdlet accepts the following parameters.

The default is ASCII.

This parameter was introduced in Windows PowerShell 3.0.

Inputs:

[System.String]: You can pipe a string that contains a path to Import-CSV.

Outputs:

[Object]: This cmdlet returns the objects described by the content in the CSV file.

Let's come back to the script. Once we get the contents of the CSV file in the $userInformation object, we process each row and assign the first name, last name, department, and office to the variables. On line 14, we call the generateUserName function and capture the return value in the variable and display the username on the script:

In this chapter, we discussed how PowerShell is a cmdlet-based language with verb-noun syntax. We covered how to pass parameters to cmdlets and store results as variables. We covered how to get help with PowerShell. We covered object-oriented concepts with PowerShell and the concept of objects. We covered how to use the if and where statements. We covered how to use the for and while loops. Finally, we created our first script and used the concepts we covered in the earlier sections to read the contents from a CSV file. In the next chapter, we will cover how can manage Office 365 using PowerShell.